The Effect of Different Hormones and Antibiotics on Activity of AST Enzyme and its Isozymes in Wistar Rats

Abstract

Background: One of the valuable tests for diagnosis of cardiovascular and liver diseases is measuring of AST activity. One of the main enzymes of transaminases group is aspartate aminotransferase. Previous Studies have shown that some alteration may occur in mitochondria function as the result of different disease or taking different medication; these changes in mitochondrial and cytosolic AST isozymes can be the sign of disorders. According to the role of steroid hormone in induction of its effects on protein synthesis genes, this study is conducted to shed some light on mechanisms and the interference of steroid hormones and antibiotics.Materials, Methods & Results: In this study, male Wistar rats were injected intramuscularly with Testosterone, progesterone and estradiol; while tetracycline and streptomycin injections were intraperitoneal. Testosterone, progesterone and estradiol injections were carried out in a short-term (15 days) and long-term (45 days) periods. Steroid hormones were dissolved in sesame in a way that by each injection, 0.2 mL sesame oil (containing specific amount of hormone) was injected to the rat. Control group was kept in the same condition except that their sesame oil injection contained no hormone. Tetracycline and Streptomycin injection was carried out for 5 days at 7 am and pm, at 50 mg/kg dosage intraperitoneally. In short- and long-term periods, rats were divided into four groups of 6-member. The concentrations were the same in the periods and 0.2 mL sesame oil was injected intramuscularly. 1 mg testosterone, 12 mg progesterone and 0.2 mg estradiol were intramuscularly injected to rats in group 2, 3 and 4, respectively [10]. Rats were divided into 9 six-member groups as follows: Group 1: intraperitoneal injection of 0.2 mL physiological serum; group 2: injection of 1 mg testosterone; group 3: injection of 1 mg testosterone + 50 mg/kg streptomycin; group 4: injection of 1 mg testosterone + 50 mg/kg tetracycline; group 5: injection of 0.2 mg estradiol; group 6: injection of 0.2 mg estradiol + 50 mg/kg streptomycin; group 7: injection of 0.2 mg estradiol + 50 mg/kg tetracycline; group 8: injection 50 mg/kg streptomycin; and group 9: injection of 50 mg/kg tetracycline. Serum concentration of AST enzyme was measured at the end of each period and the data were compared by SPSS software. all three steroid hormones had no significant impact on AST activity in short term. However, a significant effect was observed in long term in mean AST activities of the 4 groups. The group injected by testosterone exhibited 9% increases in comparison with the control group. Antibiotic-administrated groups showed lower activities as compared with hormone-injected groups. Steroid hormones and testosterone can enhance AST activity, in short-term and long-term, respectively by induction of protein enzyme. The second test confirmed this theory as the antibiotics decreased the AST activity enhancement by testosterone.Discussion: Based on the present study, steroid hormones can enhance the aspartate aminotransferase activity; and antibiotics can decrease the level of this liver enzyme by inhibition of polypeptide synthesis on related genes. This reaction could be due to interference of hormones and antibiotics effect which hinders the hormone effect along with the drug to activate the protein synthesis process.